Perforated record sensing device



y s. BRAND, ET AL 7 07 PERFORATED RECORD SENSING DEVICE Filed Sept. 10, 1947 m/rumr/on/ MIJUZA 770M TNVENTQRS SAMUEL BRAND cg ms E. CfyVOLLY Patented July 5, 1949 UNlTED STATES PATENT OFFICE.

PERFORATED RECORD SENSING DEVICE Samuel Brand, Binghamton, and Charles E. Connolly, Endicott, N. ll, assignors to International Business Machines Corporation,

New York,

4 Claims. 1

This invention relates to devices for sensing perforations in record cards and more particularly to devices for sensing such designations while the record cards are in motion through the card feeding mechanism of well-known accounting and statistical machines.

The principal object of the invention is to provide an improved sensing device of the type wherein the sensing of a perforation effects closure of contacts for controlling machine operations. It is desirable in such type of sensing device to provide as long a contact closure period as possible in order to insure ample time for the operation of the controlled mechanism. Generally, the period of such closure has been determined by the length of the perforation in the card and by the rate of movement of the card.

The present invention contemplates a structure in which a sensing element or finger, upon encountering a perforation in the card, drops therein and coincidentally closes a circuit connection which is reopened when the finger rides out of the perforation. The finger is so mounted that, after dropping into the perforation, it is engaged by the trailing edge of the perforation and moved therewith for a predetermined extent. This action thus'delays the time of egress of the finger and the circuit connection is prolonged correspondingly.

Other objects of the invention will be pointed out in the following description and claims and illustrated in the accompanying drawings, which disclose, by way of example, the principle of the invention and the best mode, which has been contemplated, of applying that principle.

In the drawings:

Fig. 1 is a View of the improved sensing device shown in relation to a perforated record with the card contacting part of the device riding on the imperforate portion of a card.

Fig. 2 is a position. view of the device showin the relationship of the parts upon entry of the sensing roller into a perforation.

Fig. 3 is a further view of the device showing the relationship of the parts, as the sensing roller is about to be forced out of the perforation.

Referring to the drawings, the record card feeding mechanism is diagrammatically represented by a pair of feeding rollers 53, which advance record card 25 toward the left with a continuous movement across a supporting plate ii. The card 25 which is the well-known IBM record card has perforations 1 arranged in the usual columns and rows according to the data their location represents.

In line with each column of perforations I is a sensing roller 18, which is pivoted at it on a bell crank l3 which in turn is pivoted at E4 on an arm of lever Hi. This lever has a stationary pivot rod H and carries a pin 86 extending through a slot l5 in hell crank l3. A spring extending between the bell crank l3 and lever It normally holds these parts in the relative positions shown in Fig. 1, wherein pin on lever It to rock it and bell crank l3 counter-..

clockwise. The contact points on spring 24 incidentally engage points on spring 26 to complete a circuit to energize well known devices such as printing or accumulating magnets in accordance with the particular type of accounting or statistical machine to which the invention may be applied.

As the card now continues to advance, the

perforation passes along roller l8 until its trailing edge la engages the roller. The tension of spring blade 24 is considerably greater than that of spring 2t, so that the edge 1a will rock bell crank it clockwise about its pivot 14 to the extent permitted by slot I5 to the position of Fig. 3.

Thereafter, the further movement of the card will cause edge 1a to act as a camming surface and force bell crank I3 upwardly and through pivot it rock lever ll! clockwise to its position of l and open contacts 24, 26. With bell crank it raised out of the perforation, spring 20 will snap it back to its initial position in readiness to drop into the next perforation I.

It is thus evident that contacts 24, 26, when closed, remain so for a period determined by the length of perforation plus the amplitude of hell crank it within the limits of the pin and slot connection l5, It.

While there have been shown and described and pointed out the fundamental novel features of the invention as applied to a single modification, it will be understood that various omissions and substitutions and changes in the form and details of the device illustrated and in its operation may be made by those skilled in the art without departing .from the spirit of the inven- 3 tion. It is the intention, therefore, to be limited only as indicated by the scope of the following claims.

What is claimed is:

l. A sensing device for a perforated record card comprising a lever having a pivot point, a second lever pivoted o'n an of the "first lever, and oscillatable therein, means for delimiting the range of said oscillation, a spring for normally holding the second lever at one end of its range, spring means biasing the first lever to cause the second lever to bear against the surface of a moving record card in whieh there may be a perforation in line with said second lever, said second lever upon encountering a hole, being urged therein by said biasing means, whereby the first lever will rock, the trailing edge of said hole thereafter engaging the second lever and oscillating it to its other limit and thereafter raising the second lever out of the perforation to rock the first lever back to its initial position,

whereby the period during which the first lever is rocked is measured by the length of the perforation and the amplitude of the range of the second lever.

2. A sensing device for a perforated record card comprising a sensing finger, a supporting arm, said arm having a stationary pivot and said sensing finger being pivoted on's'ai'd arm and oscillatable thereon, a device to limit the amplitude of such oscillation, resilient means for normally holding the finger at one of its limits, spring means normally biasing the am about its pivot to urge the finger aga'in'st a moving record card in which perforations are located to pass said finger, said spring acting upon arrival of a perforati'on at the finger to rock the finger into the perforation, continued movement of the card causing the trailing edge of the perforation to engage the finger and rock it against its resilient means to its other limit and thereafter raise the "finger out of the perforation against the action of said spring means, said resilient means thereupon acting to rock the finger backto its first Iii-nit osition, whereby the period during" which the arm is rocked is determined by the length of the perforation plus the amplitude of the oscillator of the finger.

3. A sensing device for a perforated record card comprising a. sensing finger having one end resting upon the surface of a moving record card in which perforations are located to pass said end, a pivot for the finger, spring means for biasing the finger against the card, occurrence of a perforation at the finger end causing the finger to drop into the perforation and move said pivot toward the card, continued movement of the card causing the trailing edge of the perforation to engage and rock the finger about its pivot, means for limiting the extent to which the finger is so rocked, the trailing edge being effective upon reaching said limit to force the finger out of the perforation and shift the pivot away from the card, whereby the period within which the pivot is moved toward the card and then back again is measured by the length of the perforation plus the extent to which the finger is rocked.

4. In a device of the class described, a sensing finger, means for moving a perforated record card to pass said finger, means for causing the finger to drop into a perforation in said card as the same passes the "finger, said finger being mounted to travel with the card under action of the trailing edge of a perforation into which the finger has dropped, for a predetermined extent, and then forced out of the perforation by the card, contacts controlled by the finger to close when the finger dr'ops into the hole and to open when the finger leaves the hole, whereby the duration of closure of said contacts is measured by the length of the perforation plus the extent to which the finger travels with the card.

SAMUEL BRAND. CHARLES E. CONNOLLY.

REFERENCES CITED The following referenlces are of record in the file of this patent:

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